Electromechanical transducer

Abstract

When the initial displacement greatly varies among cells in an element, there is a need to reduce a bias voltage to be applied between electrodes. This decreases the sensitivity. An electromechanical transducer of the present invention includes an element having a plurality of cells. Each of the cells includes a first electrode and a second electrode that are provided with a cavity being disposed therebetween. A groove is provided at a position at a predetermined distance from the cavity of the cell on the outermost periphery of the element.

1 . A method for preparing an electromechanical transducer comprising an element including a plurality of cells, the cells each including a first electrode, a second electrode provided with a cavity being disposed between the first electrode and a vibrating film to be deformed by a potential difference between the first electrode and the second electrode, comprising the step of:
 forming a groove at a predetermined position distant from the cavity of the cell provided on the outermost periphery of the element, such that when the element is deformed by a potential difference between the first electrode and the second electrode, a difference in displacement amount between an outermost cell of the plurality of cells and an innermost cell of the plurality of cells is less than the displacement amount when the groove is not provided.   
     
     
         2 . The method for preparing an electromechanical transducer according to  claim 1 , wherein the groove is provided in a thin film that forms a vibrating film. 
     
     
         3 . The method for preparing an electromechanical transducer according to  claim 2 , wherein the groove penetrates the thin film into a support portion configured to support the thin film. 
     
     
         4 . The method for preparing an electromechanical transducer according to  claim 1 , wherein the groove is formed on a position that the predetermined distance from the cavity of the cell on the outermost periphery of the element is shorter than or equal to a distance between the cavities of the cells. 
     
     
         5 . The method for preparing an electromechanical transducer according to  claim 2 , wherein the groove is also provided in a portion of the thin film between the cavities. 
     
     
         6 . The method for preparing an electromechanical transducer according to  claim 1 , wherein the groove continuously extends on an outer side of the cell on the outermost periphery of the element. 
     
     
         7 . A method for preparing an electromechanical transducer comprising an element including a plurality of cells, the cells each including a first electrode and a second electrode provided with a cavity being disposed between the first electrode, comprising the step of:
 forming a groove at a predetermined position distant from the cavity of the cell provided on the outermost periphery of the element, wherein the length of the groove, in a direction parallel to the surface on which the cells are arranged, is longer than the length of the cavity.   
     
     
         8 . The method for preparing an electromechanical transducer according to  claim 7 , wherein the groove is formed on the thin film that forms the vibrating film to be deformed by a potential difference between the first electrode and the second electrode. 
     
     
         9 . The method for preparing an electromechanical transducer according to  claim 8 , wherein the groove penetrates the thin film into a support portion configured to support the thin film. 
     
     
         10 . The method for preparing an electromechanical transducer according to  claim 7 , wherein the groove is formed on a position that the predetermined distance from the cavity of the cell on the outermost periphery of the element is shorter than or equal to a distance between the cavities of the cells. 
     
     
         11 . The method for preparing an electromechanical transducer according to  claim 8 , wherein the groove is also provided in a portion of the thin film between the cavities. 
     
     
         12 . The method for preparing an electromechanical transducer according to  claim 1 , wherein the groove continuously extends on an outer side of the cell on the outermost periphery of the element.